AS/NZS 4600:2018 Cold-formed steel structures
SECTION 1 SCOPE AND GENERAL
1.1 SCOPE (thickness)
220.127.116.11 Ductility (fu/fy ratio)
1.6 DESIGN REQUIREMENTS
1.6.3(a) Design capacity
Table 1.6 (b),(c),(d),(e),(f)
SECTION 2 ELEMENTS
2.1 SECTION PROPERTIES
2.1.2 Design procedures
18.104.22.168 Full section properties
22.214.171.124 Effective section properties
(b) local instabilities
2.1.3 Dimensional limits
126.96.36.199 Maximum flat-width-to-thickness ratios
188.8.131.52 Maximum web depth-to-thickness ratio
(a) unreinforced webs
2.2 EFFECTIVE WIDTHS OF STIFFENED ELEMENTS
2.2.1 Uniformly compressed stiffened elements
184.108.40.206 Effective width for capacity calculations
220.127.116.11 Effective width for deflection calculations
(a) Procedure I
2.2.3 Stiffened elements with stress gradient
18.104.22.168 Effective width for capacity calculations
22.214.171.124 Effective width for deflection calculations
2.3 EFFECTIVE WIDTHS OF UNSTIFFENED ELEMENTS
2.3.1 Uniformly compressed unstiffened elements
126.96.36.199 Effective width for capacity calculations
188.8.131.52 Effective width for deflection calculations
2.3.2 Unstiffened elements and edge stiffeners with stress gradient
184.108.40.206 Effective width for capacity calculations
220.127.116.11 Effective width for deflection calculations
2.4 EFFECTIVE WIDTH OF UNIFORMLY COMPRESSED ELEMENTS WITH AN EDGE STIFFENER
2.4.2 Effective width for capacity calculations
2.4.3 Effective width for deflection calculations
SECTION 3 MEMBERS
3.2 MEMBERS SUBJECT TO AXIAL TENSION
3.2.1 Design for axial tension
3.2.2 Nominal section capacity
3.2.3 Distribution of forces
18.104.22.168 End connections providing uniform force distribution
22.214.171.124 End connections providing non-uniform force distribution
3.3 MEMBERS SUBJECT TO BENDING
3.3.1 Bending moment
3.3.2 Nominal section moment capacity
126.96.36.199 Based on initiation of yielding
3.3.3 Nominal member moment capacity
188.8.131.52 Members subject to lateral buckling
184.108.40.206.1 Open section members
220.127.116.11.2 Closed box members
18.104.22.168 Members subject to distortional buckling
22.214.171.124 Beams having one flange through-fastened to sheeting
126.96.36.199 Shear capacity of webs without holes
3.3.5 Combined bending and shear
3.4 CONCENTRICALLY LOADED COMPRESSION MEMBERS
3.4.2 Singly-symmetric sections subject to distortional buckling
3.4.3 Columns with one flange through-fastened to sheeting
3.5 COMBINED AXIAL COMPRESSION OR TENSION, AND BENDING
3.5.1 Combined axial compression and bending
3.5.2 Combined axial tension and bending
3.6 CYLINDRICAL TUBULAR MEMBERS
3.6.4 Combined bending and compression
APPENDIX B METHODS OF ANALYSIS
B3 Second order elastic analysis
APPENDIX D BUCKLING STRESSES AND MOMENTS AND SHEARS FOR SECTIONS IN COMPRESSION, BENDING AND SHEAR
D1 MEMBERS IN COMPRESSION
D1.1 Global buckling stresses
D1.1.1 Compression members without holes
D188.8.131.52 Sections not subject to torsional or flexural-torsional buckling
D184.108.40.206 Doubly or singly-symmetric sections subject to torsional or flexural-torsional buckling
D220.127.116.11 Point-symmetric sections
D18.104.22.168 Non-symmetric sections
D1.2 Distortional buckling stresses
D1.2.1 Compression members without holes
D22.214.171.124 General channels in compression
D126.96.36.199 Simple lipped channels in compression
D2 MEMBERS IN BENDING
D2.1 Global buckling moments
D2.1.1 Members in bending without holes
D188.8.131.52 Singly, doubly and point symmetric sections
D184.108.40.206 Point symmetric Z sections
D2.2 Distortional buckling stresses
D2.2.1 Members in bending without holes
fy and fu are read directly from section properties. No reductions or increases in fy from Clause 220.127.116.11 - Strength increase resulting from cold forming.
Shapes with intermediate stiffeners and stiffened lips are not supported. If they are used then the resulting design or check will be conservative because the effect of the stiffeners will not have been taken into account.
Unlipped (plain) Cee flanges are assumed to be an unstiffened element and the web a stiffened element.
Webs of top hats that have edge stiffened bottom flanges are assumed to be a stiffened element (ie. flanges are assumed to provide sufficient edge support to the web to have the web classified as stiffened).
A ratio of effective section I to gross section I is included in the design report to provide a deflection factor approximating the increase in gross section deflections at the reported design load forces and moments. The SPACE GASS analysis deflections are based on gross sections.
Clause 1.3.39 - a single lateral restraint 'L' not combined with any other flange restraint is not recognised as an effective restraint for a segment as they do not meet the requirements of a partially retrained cross section for a segment.
Clause 1.3.39 - a continuous lateral restraint 'C' is recognised as a restraint and assumed to meet the requirements of a partially restrained cross section for a segment.
Clause 2.1.1 - full section properties and yield strengths read directly from section properties.
Clause 18.104.22.168 - actual shape including bends is used to calculate effective section properties.
Clause 22.214.171.124 - failure if elements exceed prescribed ratios, warning given if elements exceed clause note's ratios.
Clause 126.96.36.199 - shear lag effects not considered. A warning given if group length < 30 * flange width.
Clause 188.8.131.52 - procedure I used, Procedure II not used.
Clause 184.108.40.206 - it is assumed (a) and (b) are satisfied for concentric end connections.
Clause 220.127.116.11 - for channels connected by flanges only, it is assumed b(i) and b(ii) are satisfied.
Clause 18.104.22.168.1(b) - Iyc for zeds taken as geometric axis Iy/2.
Clause 22.214.171.124 - section moment capacity based on inelastic reserve capacity NOT considered.
Clause 3.3.3 - unequal angles, equation D126.96.36.199(4) used for bending in x and y axis.
Clause 3.3.3 - Mo is NOT calculated using a rational flexural-torsional buckling analysis.
Clause 188.8.131.52 - only lipped cee, lipped cee back to back and zed sections considered for distortional buckling .
Clause 184.108.40.206.1(a) - alternative for Z-sections restrained by sheeting against lateral movement NOT considered.
Clause 220.127.116.11 - only (i),(ii),(iii),(iv),(v),(vii)(vii based on group length) requirements are checked, assumed other requirements checked by user.
Clause 18.104.22.168 - no shear buckling check on CHS sections.
Clause 3.3.4 - for top hat sections, shear in x axis carried by top flange and horizontal component of web, shear in y axis carried by vertical component of the web.
Clause 3.4.1 - holes have not been allowed for in the calculation of Ae for Nc.
Clause 3.4.1 - clause notes not applied. User to specify effective lengths in steel member design group properties.
Clause 3.4.2- only lipped single or back to back cee considered for axial compression distortional buckling.
Clause 3.4.2 - fod calculated using Appendix D1.2.
Clause 3.4.3 - s = 0.5 (fastener in center of flange), smallest flange width used for zed sections.
Clause 3.4.3 - only (i),(ii),(iii),(iv),(v),(vi),(ix),(x based on group length) requirements are checked, assumed other requirements checked by user.
Clause 3.5 - equations 3.5.1(2) and 3.5.2(2) are included in section checks. Msx and Msy are used in equation 3.5.1(2)for the section check.
Clause 3.5.1 - equations 3.5.1(1) and 3.5.1(2) are included in member checks, equation 3.5.1(3) is used if N*/phicNc <= 0.15.
Clause 3.5.1 - actual group length used for L in the L/1000 centroid shift for angles.
Clause 3.5.2 - equation 3.5.2(1) is included in member checks only.
Clause 3.5.2 - equation 3.5.2(1) the axial tension term is conservatively ignored (N* is always zero) if axial tension exists.
Clause 3.6.3 - axial compression section capacity for CHS is based on gross area.
Appendix D - for zeds, the widest flange is used determining flange and lip properties.
Appendix D - flange and lip properties represented as square corners and centerlines.
Appendix D22.214.171.124 - alternative equation D1.1.2(8) not considered.
Appendix D126.96.36.199 - equal angles, if no area reduction due to fy, foc based on maximum compressive length and smallest radius of gyration in either axis.
Appendix D2.2.1 - no reduction in lambda for any bracing interval.